diff --git a/benchmarks/bench_chinese.py b/benchmarks/bench_chinese.py
index 608c043..0c4a19d 100644
--- a/benchmarks/bench_chinese.py
+++ b/benchmarks/bench_chinese.py
@@ -1,12 +1,14 @@
 """Benchmark Chinese BPE training at various scales."""
+import hashlib
 import time
 from itertools import islice
 
+import complex_tokenization_fast
 from datasets import load_dataset
 
-from complex_tokenization import BPETokenizer
-from complex_tokenization.graphs.units import register_script
-from complex_tokenization.languages.chinese.graph import chinese_character_to_graph
+import complex_tokenization
+
+IMPLS = {"reference (Python)": complex_tokenization, "fast (Rust)": complex_tokenization_fast}
 
 
 def load_texts(n):
@@ -19,21 +21,28 @@ def load_texts(n):
     return [row["text"][:500] for row in islice(ds, n) if row["text"]]
 
 
-def bench(texts, num_merges=10, label=""):
+def bench(module, impl, texts, num_merges=10):
+    # Each implementation has its own script registry and BPETokenizer.
+    from importlib import import_module
+    pkg = module.__name__
+    units = import_module(f"{pkg}.graphs.units")
+    chinese = import_module(f"{pkg}.languages.chinese.graph")
+    units.register_script("Han", chinese.chinese_character_to_graph)
+
     t0 = time.perf_counter()
-    tok = BPETokenizer()
+    tok = module.BPETokenizer()
     merges = tok.train(texts, num_merges=num_merges)
     elapsed = time.perf_counter() - t0
-    per_merge = elapsed / num_merges if num_merges else 0
-    print(f"  {label:30s} {elapsed:7.3f}s  ({per_merge:.4f}s/merge, {len(merges)} merges)")
+    digest = hashlib.md5(repr(list(merges)).encode()).hexdigest()[:10]
+    print(f"  {impl:22s} {elapsed:7.3f}s  ({elapsed / num_merges:.4f}s/merge, "
+          f"{len(merges)} merges, digest={digest})")
     return elapsed
 
 
 if __name__ == "__main__":
-    register_script("Han", chinese_character_to_graph)
-
     for n in [10, 50, 100]:
         texts = load_texts(n)
-        print(f"\n--- {len(texts)} docs ---")
-        bench(texts, num_merges=10, label=f"{len(texts)} docs, 10 merges")
-        bench(texts, num_merges=50, label=f"{len(texts)} docs, 50 merges")
+        for num_merges in [10, 50]:
+            print(f"\n--- {len(texts)} docs, {num_merges} merges ---")
+            for impl, module in IMPLS.items():
+                bench(module, impl, texts, num_merges=num_merges)